topic Return a list of attributes properties in Python Questions

Return a list of attributes properties

MichaelThornton — Wed, 14 Aug 2019 23:04:36 GMT

I am attempting to write arcpy script that will iterate through an .sde connection database, finds all datasets containing polygons and the text "FFO" in the title, then selects for those and iterates through the feature_layers contained within.

I can do this with :

import arcpy
import csv
import os

csvname = r"U:\My Documents\ArcGIS\ArcPyOutputFiles\TestFile4.csv"
headers = 'Name', 'Path'
createCSV(headers, csvname, 'wb')

arcpy.env.workspace = r"V:\tools\ArcSDE\Database Connections\5 NMSO ilmnmso3gi1 ilmnmsoclass1 (Type 1) Default.sde"

datasets = arcpy.ListDatasets("*FFO*", "Feature")
datasets = [''] + datasets if datasets is not None else []

for ds in datasets:
for fc in arcpy.ListFeatureClasses("*FFO*", "Polygon", feature_dataset=ds):

path = os.path.join( ds, fc)
#print(path).

But there are multiple polygons in each feature layer, so I want to iterate through those as well. Which I can do with arcpy.da.SearchCursor() as long as the feature layers contain a similar field_name. But not all contain the word "NAME". So I thought this would work.

arcpy.env.workspace = r"V:\tools\ArcSDE\Database Connections\5 NMSO ilmnmso3gi1 ilmnmsoclass1 (Type 1) Default.sde"

datasets = arcpy.ListDatasets("*FFO*", "Feature")
datasets = [''] + datasets if datasets is not None else []

for ds in datasets:
for fc in arcpy.ListFeatureClasses("*FFO*", "Polygon", feature_dataset=ds):

path = os.path.join( ds, fc)
#print(path)

desc = arcpy.Describe(fc)

if hasattr(desc, 'name'):

              with arcpy.da.SearchCursor(fc, ['NAME']) as sc:
                  for row in sc:
                        Name = row[0]
                        Path = row[1]
                        data = Name, path
                        createCSV(data, csvname)

But it doesn't work. I want to load a csv file with a path to the data and an identifying name of each polygon contained in the feature layers, contained in the datasets. Thank you.

Re: Return a list of attributes properties

JoshuaBixby — Thu, 15 Aug 2019 02:57:47 GMT

I don't mean to harp on semantics, but mixing and matching terminology can make it hard for others to provide meaningful suggestions.

finds all datasets containing polygons

I think most would assume "datasets containing polygons" would mean polygon feature classes, the feature classes themselves. Is that what you mean, or do you mean a feature dataset containing polygon feature classes?

iterates through the feature_layers contained within

Geodatabases don't contain layers. I assume you mean iterating over feature classes within a feature dataset.

identifying name of each polygon contained in the feature layers, contained in the datasets.

Looking at your script, it appears some feature classes contain a "Name" column/field, but not all. In terms of a unique identifer for each polygon in each feature class, someone familiar with all the feature classes would have to come up with the ruleset. Outside of "Name," what other fields might hold an identifier for the record or polygon?

Re: Return a list of attributes properties

Anonymous User — Thu, 15 Aug 2019 07:41:05 GMT

Hi Michael, this sample code might work for you.

cursor = arcpy.da.SearchCursor(fc,["Column1","Column2"])

row = cursor.next()

while row:

nameValue = row.Column1

pathValue = row.Column2

-- your logic comes here -- calling create csv function.

row = cursor.next()

Re: Return a list of attributes properties

DanPatterson_Retired — Thu, 15 Aug 2019 09:15:29 GMT

could we use code formatting please to help with reading and especially to provide line numbers

/blogs/dan_patterson/2016/08/14/script-formatting

Re: Return a list of attributes properties

JoshuaBixby — Thu, 15 Aug 2019 14:50:12 GMT

This code won't work, it will generate an AttributeError because the tuple returned from the search cursor has no attribute named "NAME" or "PATH".

Re: Return a list of attributes properties

MichaelThornton — Sat, 11 Dec 2021 20:57:18 GMT

Thanks for the support here. The code below should work and it does to a point. I need a function that checks for various names the same way (if len(arcpy.ListFields(fc,"NAME"))>0:) checks for the Field_Name : 'NAME' and then assigns that to a variable(e.g FldName) to be used in the( with arcpy.da.SearchCursor(fc, ['FldName']) as sc:) call. I will need to only return the variable: 'path' if there is no appropriate Field_Name found. However, I cannot figure out why the csv function is throwing an error or putting individual letters in each cell on the row in the xl doc.

def createCSV(data, csvname, mode ='ab'):
    with open(csvname, mode) as csvfile:
        csvwriter = csv.writer(csvfile, delimiter=',')
        csvwriter.writerow(data)


import arcpy
import csv
import os


csvname = r"U:\My Documents\ArcGIS\ArcPyOutputFiles\TestFile4.csv"
headers = 'Name', 'Path'
createCSV(headers, csvname, 'wb')

arcpy.env.workspace = r"V:\tools\ArcSDE\Database Connections\5 NMSO ilmnmso3gi1 ilmnmsoclass1 (Type 1) Default.sde"

datasets = arcpy.ListDatasets("*FFO*", "Feature")
datasets = [''] + datasets if datasets is not None else []

for ds in datasets:
    for fc in arcpy.ListFeatureClasses("*FFO*", "Polygon", feature_dataset=ds):

        path = os.path.join( ds, fc)

        if len(arcpy.ListFields(fc,"NAME"))>0:
##            print(path)
            with arcpy.da.SearchCursor(fc, ['NAME']) as sc:
                for row in sc:
                    data = row[0]
                    createCSV(data, csvname)

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Re: Return a list of attributes properties

MichaelThornton — Thu, 15 Aug 2019 16:23:07 GMT

Joshua, thanks for the response. Yes I do mean iterating through datasets, and then through feature classes, and then through individual polygons which are named in the attribute table in the feature classes. Thank you.

Re: Return a list of attributes properties

JoshuaBixby — Thu, 15 Aug 2019 18:33:04 GMT

In terms of path, do you want the path relative to the EGDB? I assume you don't want a full path including the SDE connection file since there is not a one-to-one relationship between EGDBs and connection files, i.e., numerous SDE connection files in various locations can all point to the same EGDB.

Re: Return a list of attributes properties

MichaelThornton — Sat, 11 Dec 2021 20:57:21 GMT

def FindField(fc)
    if len(arcpy.ListFields(fc,"NAME"))>0:
        FldName = "NAME"
    Elif len(arcpy.ListFields(fc,"LABEL"))>0:
        FldName = "LABEL"
    Elif len(arcpy.ListFields(fc,"NOTES"))>0:
        FldName = "NOTES"
    Elif len(arcpy.ListFields(fc,"SEED_MIX"))>0:
        FldName = "SEED_MIX"
    Elif len(arcpy.ListFields(fc,"Range"))>0:
        FldName = "Range"
    Elif len(arcpy.ListFields(fc,"PROJECT_NAME"))>0:
        FldName = "PROJECT_NAME"
    Elif len(arcpy.ListFields(fc,"ORGINAL_L"))>0:
        FldName = "ORGINAL_L"
    Elif len(arcpy.ListFields(fc,"WETLAND_TYPE"))>0:
        FldName = "WETLAND_TYPE"
    Elif len(arcpy.ListFields(fc,"Dist_Type"))>0:
        FldName = "Dist_Type"
    Elif len(arcpy.ListFields(fc,"PROJECT_NAME"))>0:
        FldName = "PROJECT_NAME"
    Elif len(arcpy.ListFields(fc,"Lessee"))>0:
        FldName = "Lessee"
    Elif len(arcpy.ListFields(fc,"label"))>0:
        FldName = "label"
    Elif len(arcpy.ListFields(fc,"MINENAME"))>0:
        FldName = "MINENAME"
    Elif len(arcpy.ListFields(fc,"Project_Name"))>0:
        FldName = "Project_Name"
    Elif len(arcpy.ListFields(fc,"Plot_Name"))>0:
        FldName = "Plot_Name"
    Elif len(arcpy.ListFields(fc,"PitName"))>0:
        FldName = "PitName"
    Else‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Joshua, I believe this will answer the question as to what other possible fields exist.

and this is not exclusive, but it will do as long as I code an option to ignore printing out anything other the feature class path containing field_names not listed.

Re: Return a list of attributes properties

MichaelThornton — Thu, 15 Aug 2019 19:07:41 GMT

Correct. I am not concerned with the SDE path, only the EGDB and feature class path. My goal is to get a print out of all polygons contained in EGDB's with the text "FFO" in the title. Since there are multiple polygons within my feature classes I will need to get in there to print out the individual polys, but it is a bit tricky since there are not good data standards in place and therefore it is not obvious what fieldname contains attributes that will give me pertinent information. Otherwise it is days of digging through multiple EGDB's and feature classes.

Re: Return a list of attributes properties

JoshuaBixby — Sat, 11 Dec 2021 20:57:24 GMT

Here is a much more Pythonic way of getting your field:

def FindField(fc):
    field_list = [
        "NAME", "LABEL", "NOTES", "SEED_MIX", "Range", "PROJECT_NAME", "ORIGINAL_L",
        "WETLAND_TYPE", "Dist_Type", "Lessee", "MINENAME", "Plot_Name", "PitName", "ObjectID"
    ]
    fields = [fld.name.upper() for fld in arcpy.ListFields(fc)]
    return next(f for f in field_list if f.upper() in fields)‍‍‍‍‍‍‍

Re: Return a list of attributes properties

MichaelThornton — Thu, 15 Aug 2019 20:48:33 GMT

That is very cool, thanks. so the returned value in this case is the variable 'f' which contains the appropriate fieldName?

Re: Return a list of attributes properties

JoshuaBixby — Thu, 15 Aug 2019 22:50:12 GMT

Yes, mostly. The variable f isn't returned as much as the contents of it, which happen to be a string containing a field name.

In terms of the list of field names, your original list included fields with the same name but different capitalization. I removed the "duplicates" since I am checking for field name regardless of case.

Re: Return a list of attributes properties

Anonymous User — Wed, 28 Aug 2019 01:03:41 GMT

Just provided the sample code to read the attributes of an object with an assumption having a difficulty to read the attributes. Ignore the reply.

Re: Return a list of attributes properties

JoshuaBixby — Wed, 28 Aug 2019 02:01:10 GMT

Ravi Dhulipudi‌, it looks like you updated the code in your original reply. Unfortunately, the updated code will generate the same AttributeError of the original code. A data access search cursor (da.SearchCursor) returns a Python tuple each time it is advanced/called, and tuples don't support attribute lookup for items stored in them.

Re: Return a list of attributes properties

Anonymous User — Wed, 28 Aug 2019 02:10:25 GMT

I use (cursor = gp.searchCursor(fc, ["Col1", "Col2"])) in my current code and it works without any issues. I haven't tested with da.SearchCursor, just took it from the original question and provided as a sample code to read the attributes.